fix: ensure variable finding works properly and add unit tests for va…

…riable finding (#5535)

Co-authored-by: jaimergp <[email protected]>

conda_build/variants.py

@@ -749,7 +749,9 @@ def find_used_variables_in_text(variant, recipe_text, selectors_only=False):
             continue
         v_regex = re.escape(v)
         v_req_regex = "[-_]".join(map(re.escape, v.split("_")))
-        variant_regex = rf"\{{\s*(?:pin_[a-z]+\(\s*?['\"])?{v_regex}[^'\"]*?\}}\}}"
+        variant_regex = (
+            rf"\{{\s*(?:pin_[a-z]+\(\s*?['\"])?{v_regex}[^_0-9a-zA-Z].*?\}}\}}"
+        )
         selector_regex = rf"^[^#\[]*?\#?\s\[[^\]]*?(?<![_\w\d]){v_regex}[=\s<>!\]]"
         # NOTE: why use a regex instead of the jinja2 parser/AST?
         # One can ask the jinja2 parser for undefined variables, but conda-build moves whole

news/5535-fix-variant-finding.rst

@@ -0,0 +1,21 @@
+### Enhancements
+
+* <news item>
+
+### Bug fixes
+
+* Fixed a bug where variants were incorrectly found as being used when they matched a leading substring of
+  another variant. (#5535)
+* Fixed a bug where variants were not found when variables were used in ``pin_*`` statements. (#5535)
+
+### Deprecations
+
+* <news item>
+
+### Docs
+
+* <news item>
+
+### Other
+
+* <news item>

tests/test_variants.py

@@ -19,6 +19,7 @@
     filter_combined_spec_to_used_keys,
     find_used_variables_in_batch_script,
     find_used_variables_in_shell_script,
+    find_used_variables_in_text,
     get_package_variants,
     get_vars,
     validate_spec,
@@ -816,6 +817,68 @@ def test_get_vars():
     assert get_vars(variants) == {"nodejs"}
 
 
+@pytest.mark.parametrize(
+    "vars,text,found_vars",
+    [
+        # basic tests
+        (
+            ("python", "python_min"),
+            "{{ python }}",
+            {"python"},
+        ),
+        (
+            ("python", "python_min"),
+            "{{ python_min }}",
+            {"python_min"},
+        ),
+        # filters and other text
+        (
+            ("python", "python_min"),
+            "python {{ python_min }}",
+            {"python_min"},
+        ),
+        (
+            ("python", "python_min"),
+            "python {{ python }}",
+            {"python"},
+        ),
+        (
+            ("python", "python_min"),
+            "python {{ python|lower }}",
+            {"python"},
+        ),
+        (
+            ("python", "python_min"),
+            "{{ python_min|lower }}",
+            {"python_min"},
+        ),
+        # pin_* statements
+        (
+            ("python", "python_min"),
+            "{{ pin_compatible('python') }}",
+            {"python"},
+        ),
+        (
+            ("python", "python_min"),
+            "{{ pin_compatible('python', max_pin='x.x') }}",
+            {"python"},
+        ),
+        (
+            ("python", "python_min"),
+            "{{ pin_compatible('python_min') }}",
+            {"python_min"},
+        ),
+        (
+            ("python", "python_min"),
+            "{{ pin_compatible('python_min', max_pin='x.x') }}",
+            {"python_min"},
+        ),
+    ],
+)
+def test_find_used_variables_in_text(vars, text, found_vars):
+    assert find_used_variables_in_text(vars, text) == found_vars
+
+
 def test_find_used_variables_in_shell_script(tmp_path: Path) -> None:
     variants = ("FOO", "BAR", "BAZ", "QUX")
     (script := tmp_path / "script.sh").write_text(